diff --git a/common/actions/wallet/actionCreators.ts b/common/actions/wallet/actionCreators.ts
index 8acf32dc..f69305f3 100644
--- a/common/actions/wallet/actionCreators.ts
+++ b/common/actions/wallet/actionCreators.ts
@@ -71,7 +71,10 @@ export function setBalanceRejected(): types.SetBalanceRejectedAction {
 
 export type TSetTokenBalances = typeof setTokenBalances;
 export function setTokenBalances(payload: {
-  [key: string]: TokenValue;
+  [key: string]: {
+    balance: TokenValue;
+    error: string | null;
+  };
 }): types.SetTokenBalancesAction {
   return {
     type: TypeKeys.WALLET_SET_TOKEN_BALANCES,
diff --git a/common/actions/wallet/actionTypes.ts b/common/actions/wallet/actionTypes.ts
index 1eb64b50..e11aab99 100644
--- a/common/actions/wallet/actionTypes.ts
+++ b/common/actions/wallet/actionTypes.ts
@@ -48,7 +48,10 @@ export interface SetBalanceRejectedAction {
 export interface SetTokenBalancesAction {
   type: TypeKeys.WALLET_SET_TOKEN_BALANCES;
   payload: {
-    [key: string]: TokenValue;
+    [key: string]: {
+      balance: TokenValue;
+      error: string | null;
+    };
   };
 }
 
diff --git a/common/api/bity.ts b/common/api/bity.ts
index dc66c24d..21989135 100644
--- a/common/api/bity.ts
+++ b/common/api/bity.ts
@@ -3,8 +3,8 @@ import { checkHttpStatus, parseJSON } from './utils';
 
 export function getAllRates() {
   const mappedRates = {};
-  return _getAllRates().then((bityRates) => {
-    bityRates.objects.forEach((each) => {
+  return _getAllRates().then(bityRates => {
+    bityRates.objects.forEach(each => {
       const pairName = each.pair;
       mappedRates[pairName] = parseFloat(each.rate_we_sell);
     });
@@ -26,7 +26,7 @@ export function postOrder(
       mode,
       pair
     }),
-    headers: bityConfig.postConfig.headers
+    headers: new Headers(bityConfig.postConfig.headers)
   })
     .then(checkHttpStatus)
     .then(parseJSON);
@@ -38,7 +38,7 @@ export function getOrderStatus(orderId: string) {
     body: JSON.stringify({
       orderid: orderId
     }),
-    headers: bityConfig.postConfig.headers
+    headers: new Headers(bityConfig.postConfig.headers)
   })
     .then(checkHttpStatus)
     .then(parseJSON);
@@ -48,4 +48,4 @@ function _getAllRates() {
   return fetch(`${bityConfig.bityURL}/v1/rate2/`)
     .then(checkHttpStatus)
     .then(parseJSON);
-}
\ No newline at end of file
+}
diff --git a/common/components/BalanceSidebar/EquivalentValues.tsx b/common/components/BalanceSidebar/EquivalentValues.tsx
index 7fda3f81..40162333 100644
--- a/common/components/BalanceSidebar/EquivalentValues.tsx
+++ b/common/components/BalanceSidebar/EquivalentValues.tsx
@@ -87,6 +87,8 @@ export default class EquivalentValues extends React.Component<Props, CmpState> {
       });
     } else if (ratesError) {
       valuesEl = <h5>{ratesError}</h5>;
+    } else if (tokenBalances && tokenBalances.length === 0) {
+      valuesEl = <h5>No tokens found!</h5>;
     } else {
       valuesEl = (
         <div className="EquivalentValues-values-loader">
diff --git a/common/config/data.ts b/common/config/data.ts
index be69ac04..60a34757 100644
--- a/common/config/data.ts
+++ b/common/config/data.ts
@@ -55,6 +55,7 @@ export interface Token {
   address: string;
   symbol: string;
   decimal: number;
+  error?: string | null;
 }
 
 export interface NetworkContract {
diff --git a/common/libs/nodes/INode.ts b/common/libs/nodes/INode.ts
index 653c2c9a..b2db9a86 100644
--- a/common/libs/nodes/INode.ts
+++ b/common/libs/nodes/INode.ts
@@ -9,8 +9,14 @@ export interface TxObj {
 export interface INode {
   ping(): Promise<boolean>;
   getBalance(address: string): Promise<Wei>;
-  getTokenBalance(address: string, token: Token): Promise<TokenValue>;
-  getTokenBalances(address: string, tokens: Token[]): Promise<TokenValue[]>;
+  getTokenBalance(
+    address: string,
+    token: Token
+  ): Promise<{ balance: TokenValue; error: string | null }>;
+  getTokenBalances(
+    address: string,
+    tokens: Token[]
+  ): Promise<{ balance: TokenValue; error: string | null }[]>;
   estimateGas(tx: TransactionWithoutGas): Promise<Wei>;
   getTransactionCount(address: string): Promise<string>;
   sendRawTx(tx: string): Promise<string>;
diff --git a/common/libs/nodes/etherscan/client.ts b/common/libs/nodes/etherscan/client.ts
index 77e24965..b5b666ef 100644
--- a/common/libs/nodes/etherscan/client.ts
+++ b/common/libs/nodes/etherscan/client.ts
@@ -6,7 +6,9 @@ export default class EtherscanClient extends RPCClient {
   public encodeRequest(request: EtherscanRequest): string {
     const encoded = new URLSearchParams();
     Object.keys(request).forEach(key => {
-      encoded.set(key, request[key]);
+      if (request[key]) {
+        encoded.set(key, request[key]);
+      }
     });
     return encoded.toString();
   }
@@ -14,9 +16,9 @@ export default class EtherscanClient extends RPCClient {
   public call = (request: EtherscanRequest): Promise<JsonRpcResponse> =>
     fetch(this.endpoint, {
       method: 'POST',
-      headers: {
+      headers: new Headers({
         'Content-Type': 'application/x-www-form-urlencoded; charset=UTF-8'
-      },
+      }),
       body: this.encodeRequest(request)
     }).then(r => r.json());
 
diff --git a/common/libs/nodes/etherscan/requests.ts b/common/libs/nodes/etherscan/requests.ts
index 036cb60c..c98256a3 100644
--- a/common/libs/nodes/etherscan/requests.ts
+++ b/common/libs/nodes/etherscan/requests.ts
@@ -15,7 +15,7 @@ export default class EtherscanRequests extends RPCRequests {
   public sendRawTx(signedTx: string): SendRawTxRequest {
     return {
       module: 'proxy',
-      method: 'eth_sendRawTransaction',
+      action: 'eth_sendRawTransaction',
       hex: signedTx
     };
   }
@@ -23,7 +23,7 @@ export default class EtherscanRequests extends RPCRequests {
   public estimateGas(transaction): EstimateGasRequest {
     return {
       module: 'proxy',
-      method: 'eth_estimateGas',
+      action: 'eth_estimateGas',
       to: transaction.to,
       value: transaction.value,
       data: transaction.data,
diff --git a/common/libs/nodes/etherscan/types.ts b/common/libs/nodes/etherscan/types.ts
index fd153ba8..5fca1167 100644
--- a/common/libs/nodes/etherscan/types.ts
+++ b/common/libs/nodes/etherscan/types.ts
@@ -5,7 +5,7 @@ export interface EtherscanReqBase {
 
 export interface SendRawTxRequest extends EtherscanReqBase {
   module: 'proxy';
-  method: 'eth_sendRawTransaction';
+  action: 'eth_sendRawTransaction';
   hex: string;
 }
 
@@ -27,7 +27,7 @@ export type GetTokenBalanceRequest = CallRequest;
 
 export interface EstimateGasRequest extends EtherscanReqBase {
   module: 'proxy';
-  method: 'eth_estimateGas';
+  action: 'eth_estimateGas';
   to: string;
   value: string | number;
   data: string;
diff --git a/common/libs/nodes/infura/client.ts b/common/libs/nodes/infura/client.ts
index 536173e3..2bc400ab 100644
--- a/common/libs/nodes/infura/client.ts
+++ b/common/libs/nodes/infura/client.ts
@@ -2,7 +2,7 @@ import { randomBytes } from 'crypto';
 import RPCClient from '../rpc/client';
 
 export default class InfuraClient extends RPCClient {
-  public id(): string {
-    return `0x${randomBytes(5).toString('hex')}`;
+  public id(): number {
+    return parseInt(randomBytes(5).toString('hex'), 16);
   }
 }
diff --git a/common/libs/nodes/rpc/client.ts b/common/libs/nodes/rpc/client.ts
index 144fd2cb..7f1934ee 100644
--- a/common/libs/nodes/rpc/client.ts
+++ b/common/libs/nodes/rpc/client.ts
@@ -9,7 +9,7 @@ export default class RPCClient {
     this.headers = headers;
   }
 
-  public id(): string {
+  public id(): string | number {
     return randomBytes(16).toString('hex');
   }
 
@@ -22,10 +22,10 @@ export default class RPCClient {
   public call = (request: RPCRequest | any): Promise<JsonRpcResponse> => {
     return fetch(this.endpoint, {
       method: 'POST',
-      headers: {
+      headers: this.createHeaders({
         'Content-Type': 'application/json',
         ...this.headers
-      },
+      }),
       body: JSON.stringify(this.decorateRequest(request))
     }).then(r => r.json());
   };
@@ -33,11 +33,19 @@ export default class RPCClient {
   public batch = (requests: RPCRequest[] | any): Promise<JsonRpcResponse[]> => {
     return fetch(this.endpoint, {
       method: 'POST',
-      headers: {
+      headers: this.createHeaders({
         'Content-Type': 'application/json',
         ...this.headers
-      },
+      }),
       body: JSON.stringify(requests.map(this.decorateRequest))
     }).then(r => r.json());
   };
+
+  private createHeaders = headerObject => {
+    const headers = new Headers();
+    Object.keys(headerObject).forEach(name => {
+      headers.append(name, headerObject[name]);
+    });
+    return headers;
+  };
 }
diff --git a/common/libs/nodes/rpc/index.ts b/common/libs/nodes/rpc/index.ts
index af5acd82..005c8318 100644
--- a/common/libs/nodes/rpc/index.ts
+++ b/common/libs/nodes/rpc/index.ts
@@ -6,13 +6,15 @@ import { stripHexPrefix } from 'libs/values';
 import { INode, TxObj } from '../INode';
 import RPCClient from './client';
 import RPCRequests from './requests';
-
-function errorOrResult(response) {
-  if (response.error) {
-    throw new Error(response.error.message);
-  }
-  return response.result;
-}
+import {
+  isValidGetBalance,
+  isValidEstimateGas,
+  isValidCallRequest,
+  isValidTokenBalance,
+  isValidTransactionCount,
+  isValidCurrentBlock,
+  isValidRawTxApi
+} from '../../validators';
 
 export default class RpcNode implements INode {
   public client: RPCClient;
@@ -31,78 +33,87 @@ export default class RpcNode implements INode {
   }
 
   public sendCallRequest(txObj: TxObj): Promise<string> {
-    return this.client.call(this.requests.ethCall(txObj)).then(r => {
-      if (r.error) {
-        throw Error(r.error.message);
-      }
-      return r.result;
-    });
+    return this.client
+      .call(this.requests.ethCall(txObj))
+      .then(isValidCallRequest)
+      .then(response => response.result);
   }
   public getBalance(address: string): Promise<Wei> {
     return this.client
       .call(this.requests.getBalance(address))
-      .then(errorOrResult)
-      .then(result => Wei(result));
+      .then(isValidGetBalance)
+      .then(({ result }) => Wei(result));
   }
 
   public estimateGas(transaction: TransactionWithoutGas): Promise<Wei> {
     return this.client
       .call(this.requests.estimateGas(transaction))
-      .then(errorOrResult)
-      .then(result => Wei(result));
+      .then(isValidEstimateGas)
+      .then(({ result }) => Wei(result));
   }
 
-  public getTokenBalance(address: string, token: Token): Promise<TokenValue> {
+  public getTokenBalance(
+    address: string,
+    token: Token
+  ): Promise<{ balance: TokenValue; error: string | null }> {
     return this.client
       .call(this.requests.getTokenBalance(address, token))
-      .then(response => {
-        if (response.error) {
-          // TODO - Error handling
-          return TokenValue('0');
-        }
-        return TokenValue(response.result);
-      });
+      .then(isValidTokenBalance)
+      .then(({ result }) => {
+        return {
+          balance: TokenValue(result),
+          error: null
+        };
+      })
+      .catch(err => ({
+        balance: TokenValue('0'),
+        error: 'Caught error:' + err
+      }));
   }
 
   public getTokenBalances(
     address: string,
     tokens: Token[]
-  ): Promise<TokenValue[]> {
+  ): Promise<{ balance: TokenValue; error: string | null }[]> {
     return this.client
       .batch(tokens.map(t => this.requests.getTokenBalance(address, t)))
-      .then(response => {
-        return response.map(item => {
-          // FIXME wrap in maybe-like
-          if (item.error) {
-            return TokenValue('0');
+      .then(response =>
+        response.map(item => {
+          if (isValidTokenBalance(item)) {
+            return {
+              balance: TokenValue(item.result),
+              error: null
+            };
+          } else {
+            return {
+              balance: TokenValue('0'),
+              error: 'Invalid object shape'
+            };
           }
-          return TokenValue(item.result);
-        });
-      });
-    // TODO - Error handling
+        })
+      );
   }
 
   public getTransactionCount(address: string): Promise<string> {
     return this.client
       .call(this.requests.getTransactionCount(address))
-      .then(errorOrResult);
+      .then(isValidTransactionCount)
+      .then(({ result }) => result);
   }
 
   public getCurrentBlock(): Promise<string> {
     return this.client
       .call(this.requests.getCurrentBlock())
-      .then(errorOrResult)
-      .then(result => new BN(stripHexPrefix(result)).toString());
+      .then(isValidCurrentBlock)
+      .then(({ result }) => new BN(stripHexPrefix(result)).toString());
   }
 
   public sendRawTx(signedTx: string): Promise<string> {
     return this.client
       .call(this.requests.sendRawTx(signedTx))
-      .then(response => {
-        if (response.error) {
-          throw new Error(response.error.message);
-        }
-        return response.result;
+      .then(isValidRawTxApi)
+      .then(({ result }) => {
+        return result;
       });
   }
 }
diff --git a/common/libs/nodes/web3/index.ts b/common/libs/nodes/web3/index.ts
index 47a4de75..64d77690 100644
--- a/common/libs/nodes/web3/index.ts
+++ b/common/libs/nodes/web3/index.ts
@@ -57,7 +57,13 @@ export default class Web3Node implements INode {
     );
   }
 
-  public getTokenBalance(address: string, token: Token): Promise<TokenValue> {
+  public getTokenBalance(
+    address: string,
+    token: Token
+  ): Promise<{
+    balance: TokenValue;
+    error: string | null;
+  }> {
     return new Promise(resolve => {
       this.web3.eth.call(
         {
@@ -68,10 +74,10 @@ export default class Web3Node implements INode {
         (err, res) => {
           if (err) {
             // TODO - Error handling
-            return resolve(TokenValue('0'));
+            return resolve({ balance: TokenValue('0'), error: err });
           }
           // web3 returns string
-          resolve(TokenValue(res));
+          resolve({ balance: TokenValue(res), error: null });
         }
       );
     });
@@ -80,11 +86,14 @@ export default class Web3Node implements INode {
   public getTokenBalances(
     address: string,
     tokens: Token[]
-  ): Promise<TokenValue[]> {
+  ): Promise<{ balance: TokenValue; error: string | null }[]> {
     return new Promise(resolve => {
       const batch = this.web3.createBatch();
       const totalCount = tokens.length;
-      const returnArr = new Array<TokenValue>(totalCount);
+      const returnArr = new Array<{
+        balance: TokenValue;
+        error: string | null;
+      }>(totalCount);
       let finishCount = 0;
 
       tokens.forEach((token, index) =>
@@ -104,10 +113,16 @@ export default class Web3Node implements INode {
       function finish(index, err, res) {
         if (err) {
           // TODO - Error handling
-          returnArr[index] = TokenValue('0');
+          returnArr[index] = {
+            balance: TokenValue('0'),
+            error: err
+          };
         } else {
           // web3 returns string
-          returnArr[index] = TokenValue(res);
+          returnArr[index] = {
+            balance: TokenValue(res),
+            error: err
+          };
         }
 
         finishCount++;
diff --git a/common/libs/validators.ts b/common/libs/validators.ts
index 6fd91e7c..fff82e5e 100644
--- a/common/libs/validators.ts
+++ b/common/libs/validators.ts
@@ -2,6 +2,8 @@ import { toChecksumAddress } from 'ethereumjs-util';
 import { RawTransaction } from 'libs/transaction';
 import WalletAddressValidator from 'wallet-address-validator';
 import { normalise } from './ens';
+import { Validator } from 'jsonschema';
+import { JsonRpcResponse } from './nodes/rpc/types';
 
 export function isValidETHAddress(address: string): boolean {
   if (!address) {
@@ -177,3 +179,67 @@ export const isValidByteCode = (byteCode: string) =>
 
 export const isValidAbiJson = (abiJson: string) =>
   abiJson && abiJson.startsWith('[') && abiJson.endsWith(']');
+
+// JSONSchema Validations for Rpc responses
+const v = new Validator();
+
+export const schema = {
+  RpcNode: {
+    type: 'object',
+    additionalProperties: false,
+    properties: {
+      jsonrpc: { type: 'string' },
+      id: { oneOf: [{ type: 'string' }, { type: 'integer' }] },
+      result: { type: 'string' },
+      status: { type: 'string' },
+      message: { type: 'string', maxLength: 2 }
+    }
+  }
+};
+
+function isValidResult(response: JsonRpcResponse, schemaFormat): boolean {
+  return v.validate(response, schemaFormat).valid;
+}
+
+function formatErrors(response: JsonRpcResponse, apiType: string) {
+  if (response.error) {
+    return `${response.error.message} ${response.error.data}`;
+  }
+  return `Invalid ${apiType} Error`;
+}
+
+const isValidEthCall = (response: JsonRpcResponse, schemaType) => (
+  apiName,
+  cb?
+) => {
+  if (!isValidResult(response, schemaType)) {
+    if (cb) {
+      return cb(response);
+    }
+    throw new Error(formatErrors(response, apiName));
+  }
+  return response;
+};
+
+export const isValidGetBalance = (response: JsonRpcResponse) =>
+  isValidEthCall(response, schema.RpcNode)('Get Balance');
+
+export const isValidEstimateGas = (response: JsonRpcResponse) =>
+  isValidEthCall(response, schema.RpcNode)('Estimate Gas');
+
+export const isValidCallRequest = (response: JsonRpcResponse) =>
+  isValidEthCall(response, schema.RpcNode)('Call Request');
+
+export const isValidTokenBalance = (response: JsonRpcResponse) =>
+  isValidEthCall(response, schema.RpcNode)('Token Balance', () => ({
+    result: 'Failed'
+  }));
+
+export const isValidTransactionCount = (response: JsonRpcResponse) =>
+  isValidEthCall(response, schema.RpcNode)('Transaction Count');
+
+export const isValidCurrentBlock = (response: JsonRpcResponse) =>
+  isValidEthCall(response, schema.RpcNode)('Current Block');
+
+export const isValidRawTxApi = (response: JsonRpcResponse) =>
+  isValidEthCall(response, schema.RpcNode)('Raw Tx');
diff --git a/common/reducers/wallet.ts b/common/reducers/wallet.ts
index 83a021c5..59242c46 100644
--- a/common/reducers/wallet.ts
+++ b/common/reducers/wallet.ts
@@ -15,7 +15,10 @@ export interface State {
   // in ETH
   balance: Balance | { wei: null };
   tokens: {
-    [key: string]: TokenValue;
+    [key: string]: {
+      balance: TokenValue;
+      error: string | null;
+    };
   };
   transactions: BroadcastTransactionStatus[];
 }
diff --git a/common/selectors/wallet.ts b/common/selectors/wallet.ts
index f2d36f5e..1e52d01b 100644
--- a/common/selectors/wallet.ts
+++ b/common/selectors/wallet.ts
@@ -14,6 +14,7 @@ export interface TokenBalance {
   balance: TokenValue;
   custom: boolean;
   decimal: number;
+  error: string | null;
 }
 
 export type MergedToken = Token & {
@@ -38,8 +39,11 @@ export function getTokenBalances(state: AppState): TokenBalance[] {
   return tokens.map(t => ({
     symbol: t.symbol,
     balance: state.wallet.tokens[t.symbol]
-      ? state.wallet.tokens[t.symbol]
+      ? state.wallet.tokens[t.symbol].balance
       : TokenValue('0'),
+    error: state.wallet.tokens[t.symbol]
+      ? state.wallet.tokens[t.symbol].error
+      : null,
     custom: t.custom,
     decimal: t.decimal
   }));
diff --git a/common/utils/printElement.ts b/common/utils/printElement.ts
index a1dbadef..207bfa26 100644
--- a/common/utils/printElement.ts
+++ b/common/utils/printElement.ts
@@ -26,8 +26,9 @@ export default function(
     .join(',');
 
   const popup = window.open('about:blank', 'printWindow', featuresStr);
-  popup.document.open();
-  popup.document.write(`
+  if (popup) {
+    popup.document.open();
+    popup.document.write(`
   <html>
     <head>
       <style>${options.styles}</style>
@@ -50,4 +51,5 @@ export default function(
     </body>
     </html>
 	`);
+  }
 }
diff --git a/jest_config/setupJest.js b/jest_config/setupJest.js
index 7c59e8ed..07c52109 100644
--- a/jest_config/setupJest.js
+++ b/jest_config/setupJest.js
@@ -1,2 +1,17 @@
-global.fetch = require('node-fetch')
-window.BASE_API = 'http://localhost:4000/api/v1'
+'use strict';
+
+var realFetch = require('node-fetch');
+module.exports = function(url, options) {
+  if (/^\/\//.test(url)) {
+    url = 'https:' + url;
+  }
+  return realFetch.call(this, url, options);
+};
+
+if (!global.fetch) {
+  global.fetch = module.exports;
+  global.Response = realFetch.Response;
+  global.Headers = realFetch.Headers;
+  global.Request = realFetch.Request;
+}
+window.BASE_API = 'http://localhost:4000/api/v1';
diff --git a/package.json b/package.json
index db241ccb..002cd484 100644
--- a/package.json
+++ b/package.json
@@ -20,6 +20,7 @@
     "font-awesome": "4.7.0",
     "hdkey": "0.7.1",
     "idna-uts46": "1.1.0",
+    "jsonschema": "1.2.0",
     "lodash": "4.17.4",
     "moment": "2.19.3",
     "qrcode": "1.0.0",
@@ -104,6 +105,7 @@
     "types-rlp": "0.0.1",
     "typescript": "2.5.2",
     "url-loader": "0.6.2",
+    "url-search-params-polyfill": "2.0.1",
     "webpack": "3.8.1",
     "webpack-dev-middleware": "1.12.2",
     "webpack-hot-middleware": "2.21.0"
diff --git a/spec/config/RpcNodeTestConfig.js b/spec/config/RpcNodeTestConfig.js
new file mode 100644
index 00000000..998645c8
--- /dev/null
+++ b/spec/config/RpcNodeTestConfig.js
@@ -0,0 +1,5 @@
+module.exports = {
+  RpcNodes: ['eth_mew', 'etc_epool', 'etc_epool', 'rop_mew'],
+  EtherscanNodes: ['eth_ethscan', 'kov_ethscan', 'rin_ethscan'],
+  InfuraNodes: ['eth_infura', 'rop_infura', 'rin_infura']
+};
diff --git a/spec/config/data.spec.ts b/spec/config/data.spec.ts
new file mode 100644
index 00000000..d02a2208
--- /dev/null
+++ b/spec/config/data.spec.ts
@@ -0,0 +1,93 @@
+import { NODES, NodeConfig } from '../../common/config/data';
+import { RPCNode } from '../../common/libs/nodes';
+import { Validator } from 'jsonschema';
+import { schema } from '../../common/libs/validators';
+import 'url-search-params-polyfill';
+import EtherscanNode from 'libs/nodes/etherscan';
+import InfuraNode from 'libs/nodes/infura';
+import RpcNodeTestConfig from './RpcNodeTestConfig';
+
+const v = new Validator();
+
+const validRequests = {
+  address: '0x72948fa4200d10ffaa7c594c24bbba6ef627d4a3',
+  transaction: {
+    data: '',
+    from: '0x72948fa4200d10ffaa7c594c24bbba6ef627d4a3',
+    to: '0x72948fa4200d10ffaa7c594c24bbba6ef627d4a3',
+    value: '0xde0b6b3a7640000'
+  },
+  token: {
+    address: '0x4156d3342d5c385a87d264f90653733592000581',
+    symbol: 'SALT',
+    decimal: 8
+  }
+};
+
+const testGetBalance = (n: RPCNode) => {
+  return n.client
+    .call(n.requests.getBalance(validRequests.address))
+    .then(data => v.validate(data, schema.RpcNode));
+};
+
+const testEstimateGas = (n: RPCNode) => {
+  return n.client
+    .call(n.requests.estimateGas(validRequests.transaction))
+    .then(data => v.validate(data, schema.RpcNode));
+};
+
+const testGetTokenBalance = (n: RPCNode) => {
+  const { address, token } = validRequests;
+  return n.client
+    .call(n.requests.getTokenBalance(address, token))
+    .then(data => v.validate(data, schema.RpcNode));
+};
+
+const RPCTests = {
+  getBalance: testGetBalance,
+  estimateGas: testEstimateGas,
+  getTokenBalance: testGetTokenBalance
+};
+
+function testRpcRequests(node: RPCNode, service: string) {
+  Object.keys(RPCTests).forEach(testType => {
+    describe(`RPC (${service}) should work`, () => {
+      it(
+        `RPC: ${testType} ${service}`,
+        () => {
+          return RPCTests[testType](node).then(d =>
+            expect(d.valid).toBeTruthy()
+          );
+        },
+        10000
+      );
+    });
+  });
+}
+
+const mapNodeEndpoints = (nodes: { [key: string]: NodeConfig }) => {
+  const { RpcNodes, EtherscanNodes, InfuraNodes } = RpcNodeTestConfig;
+
+  RpcNodes.forEach(n => {
+    testRpcRequests(
+      nodes[n].lib as RPCNode,
+      `${nodes[n].service} ${nodes[n].network}`
+    );
+  });
+
+  EtherscanNodes.forEach(n => {
+    testRpcRequests(
+      nodes[n].lib as EtherscanNode,
+      `${nodes[n].service} ${nodes[n].network}`
+    );
+  });
+
+  InfuraNodes.forEach(n => {
+    testRpcRequests(
+      nodes[n].lib as InfuraNode,
+      `${nodes[n].service} ${nodes[n].network}`
+    );
+  });
+};
+
+mapNodeEndpoints(NODES);
diff --git a/spec/pages/__snapshots__/SendTransaction.spec.tsx.snap b/spec/pages/__snapshots__/SendTransaction.spec.tsx.snap
index 51777a68..7bba85ab 100644
--- a/spec/pages/__snapshots__/SendTransaction.spec.tsx.snap
+++ b/spec/pages/__snapshots__/SendTransaction.spec.tsx.snap
@@ -56,6 +56,7 @@ exports[`render snapshot 1`] = `
       "client": RPCClient {
         "batch": [Function],
         "call": [Function],
+        "createHeaders": [Function],
         "decorateRequest": [Function],
         "endpoint": "https://api.myetherapi.com/rop",
         "headers": Object {},
diff --git a/spec/reducers/wallet.spec.ts b/spec/reducers/wallet.spec.ts
index a12b039a..e87d661a 100644
--- a/spec/reducers/wallet.spec.ts
+++ b/spec/reducers/wallet.spec.ts
@@ -60,7 +60,16 @@ describe('wallet reducer', () => {
   });
 
   it('should handle WALLET_SET_TOKEN_BALANCES', () => {
-    const tokenBalances = { OMG: TokenValue('20') };
+    const tokenBalances = {
+      OMG: {
+        balance: TokenValue('20'),
+        error: null
+      },
+      WTT: {
+        balance: TokenValue('0'),
+        error: 'The request failed to execute'
+      }
+    };
     expect(
       wallet(undefined, walletActions.setTokenBalances(tokenBalances))
     ).toEqual({
diff --git a/spec/sagas/__snapshots__/deterministicWallets.spec.ts.snap b/spec/sagas/__snapshots__/deterministicWallets.spec.ts.snap
index 45760707..63dc34b7 100644
--- a/spec/sagas/__snapshots__/deterministicWallets.spec.ts.snap
+++ b/spec/sagas/__snapshots__/deterministicWallets.spec.ts.snap
@@ -178,6 +178,7 @@ Object {
           "client": RPCClient {
             "batch": [Function],
             "call": [Function],
+            "createHeaders": [Function],
             "decorateRequest": [Function],
             "endpoint": "",
             "headers": Object {},
@@ -202,6 +203,7 @@ Object {
           "client": RPCClient {
             "batch": [Function],
             "call": [Function],
+            "createHeaders": [Function],
             "decorateRequest": [Function],
             "endpoint": "",
             "headers": Object {},